The effect of vitamin D level on body composition and metabolic parameters in adults with different body mass index

Abstract

The aim of this study was to describe the relationship between serum 25 (OH) vitamin D and anthropometric and metabolic parameters in adult patients with different BMI.The cross-sectional study was conducted between November 2018 and May 2019 with 224 participants. Body weight, height and blood pressure of the individuals includedin the study were recorded. Body composition was evaluated by bioelectrical impedance (BIA) on a Tanita BC 420 MA analyzer (Tanita Inc., Japan). Serum 25 (OH)D, fasting insulin level, fasting blood glucose, HDL-cholesterol and triglycerides were measured. Insulin resistance index was calculated (HOMA-IR). Statistical analysiswas performed on an IBM SPSS Statistics 22 (Chicago, IL) for the Windows platform. The mean age of the 224 participants (176 females, 48 males) was 36.6 ± 7.9. 36(16%) of the participants had normal BMI, 67 (29.9%) were overweight and 121 (54%) had obesity. Women had higher levels of fat, fat percentage, LDL-C, and BMI thanmen. FPG, LDL-C, and HOMA-IR were lower in patients with normal BMI, but differences between high BMI categories were significant only in fasting plasma glucose.Vitamin D was inversely and weakly associated with most of the parameters. It showed a significant correlation between vitamin D and more parameters in males thanfemales. Serum vitamin D was negatively correlated with weight and HDL-C only in obese subjects, whereas it was negatively correlated with age and SBP in subjectswith normal BMI. In overweight participants, vitamin D did not correlate with any of the other parameters. Vitamin D deficiency and insufficient are very common inpatients with poor metabolic health, although the relationship at individual level is not always present. Therefore, vitamin D supplementation should be considered as atherapeutic option in all subjects who are overweight, obesity and metabolic disorders.